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Abstract Coloration is an important phenotypic trait for taxonomic studies and has been widely used for identifying insect species and populations. However, coloration can be a poor diagnostic character for insect species that exhibit high polymorphism in this trait, which can lead to over-splitting of taxonomic units. In orchid bees, color variation has been interpreted by different taxonomists as either polymorphism associated with Müllerian mimicry complexes or diagnostic traits for species identification. Despite this uncertainty, integrative approaches that incorporate multiple independent datasets to test the validity of hair coloration as a character that identifies independent evolutionary units have not been used. Here, we use phylogenomic data from Ultraconserved Elements (UCEs) to explore whether color phenotypes in the widespread orchid bee species complexes Eulaema meriana and Eulaema bombiformis (Hymenoptera: Apidae: Euglossini) correspond to independent lineages or polymorphic trait variation within species. We find that lineages within both species are structured according to geography and that color morphs are generally unassociated with evolutionarily independent groups except for populations located in the Atlantic Forest of Brazil. We conclude that there is compelling evidence that E. atleticana and E. niveofasciata are subspecies of E. meriana and E. bombiformis, respectively, and not different species as previously suggested. Therefore, we recognize Eulaema meriana atleticanacomb. n. and Eulaema bombiformis niveofasciatacomb. n. and discuss their morphological characteristics. We make recommendations on the use of color traits for orchid bee taxonomy and discuss the significance of subspecies as evolutionary units relevant for conservation efforts. 

Abstract The advent of community-science databases in conjunction with museum specimen locality information has exponentially increased the power and accuracy of ecological niche modeling (ENM). Increased occurrence data has provided colossal potential to understand the distributions of lesser known or endangered species, including arthropods. Although niche modeling of termites has been conducted in the context of invasive and pest species, few studies have been performed to understand the distribution of basal termite genera. Using specimen records from the American Museum of Natural History (AMNH) as well as locality databases, we generated ecological niche models for 12 basal termite species belonging to six genera and three families. We extracted environmental data from the Worldclim 19 bioclimatic dataset v2, along with SoilGrids datasets and generated models using MaxEnt. We chose Optimal models based on partial Receiving Operating characteristic (pROC) and omission rate criterion and determined variable importance using permutation analysis. We also calculated response curves to understand changes in suitability with changes in environmental variables. Optimal models for our 12 termite species ranged in complexity, but no discernible pattern was noted among genera, families, or geographic range. Permutation analysis revealed that habitat suitability is affected predominantly by seasonal or monthly temperature and precipitation variation. Our findings not only highlight the efficacy of largely community-science and museum-based datasets, but our models provide a baseline for predictions of future abundance of lesser-known arthropod species in the face of habitat destruction and climate change. 

Abstract The southern Appalachian Mountains were intensively logged during the early 1900s, leaving little remaining old-growth forest. Much of the region is now second-growth forest, which may not be suitable to specialist saproxylic species. Moreover, if suitable habitat exists, poorly dispersing species may not be able to colonize it. To investigate this, we assessed the distribution and old-growth dependency of two low-mobility saproxylic beetles in Great Smoky Mountains National Park. Using both field surveys and community science data, we found Megalodacne heros (Say 1823) (Coleoptera: Erotylidae) to be limited to lower elevations regardless of disturbance history, while Phellopsis obcordata (Kirby 1837) (Coleoptera: Zopheridae) was restricted to inside or near old-growth forests. Although trees were generally smaller in second-growth, we detected no habitat limitation for P. obcordata: fungal hosts were present in second-growth areas and the beetle was present on trees as small as 11 cm in diameter. This suggests its distribution is shaped by its low dispersal capability and need for temporal continuity of deadwood habitat, therefore qualifying it as an indicator species. For P. obcordata, old-growth acted as refugia during landscape-wide, anthropogenic disturbances in the early 1900s, though we can draw no conclusions about M. heros from our dataset. The difference in sensitivity to human disturbance displayed between species may be linked to their relative dispersal abilities: P. obcordata is entirely flightless while M. heros is capable of some flight. This study highlights the value of using saproxylic invertebrates with limited dispersal ability for assessing impacts from anthropogenic forest disturbances.